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.\" $Id$
.\"
.Dd October 5, 2025
.Dt KADMIN 8
.Os HEIMDAL
.Sh NAME
.Nm kadmin
.Nd Kerberos administration utility
.Sh SYNOPSIS
.Nm
.Bk -words
.Op Fl p Ar string \*(Ba Fl Fl principal= Ns Ar string
.Op Fl K Ar string \*(Ba Fl Fl keytab= Ns Ar string
.Op Fl c Ar file \*(Ba Fl Fl config-file= Ns Ar file
.Op Fl k Ar file \*(Ba Fl Fl key-file= Ns Ar file
.Op Fl r Ar realm \*(Ba Fl Fl realm= Ns Ar realm
.Op Fl a Ar host \*(Ba Fl Fl admin-server= Ns Ar host
.Op Fl s Ar port number \*(Ba Fl Fl server-port= Ns Ar port number
.Op Fl l | Fl Fl local
.Op Fl h | Fl Fl help
.Op Fl v | Fl Fl version
.Op Ar command
.Ek
.Sh DESCRIPTION
The
.Nm
program is used to make modifications to the Kerberos database, either remotely via the
.Xr kadmind 8
daemon, or locally (with the
.Fl l
option).
.Pp
Supported options:
.Bl -tag -width Ds
.It Fl p Ar string , Fl Fl principal= Ns Ar string
principal to authenticate as
.It Fl K Ar string , Fl Fl keytab= Ns Ar string
keytab for authentication principal
.It Fl c Ar file , Fl Fl config-file= Ns Ar file
location of config file
.It Fl k Ar file , Fl Fl key-file= Ns Ar file
location of master key file
.It Fl r Ar realm , Fl Fl realm= Ns Ar realm
realm to use
.It Fl a Ar host , Fl Fl admin-server= Ns Ar host
server to contact
.It Fl s Ar port number , Fl Fl server-port= Ns Ar port number
port to use
.It Fl l , Fl Fl local
local admin mode
.El
.Pp
If no
.Ar command
is given on the command line,
.Nm
will prompt for commands to process. Some of the commands that take
one or more principals as argument
.Ns ( Nm delete ,
.Nm ext_keytab ,
.Nm get ,
.Nm modify ,
and
.Nm passwd )
will accept a glob style wildcard, and perform the operation on all
matching principals.
.Pp
Commands include:
.\" not using a list here, since groff apparently gets confused
.\" with nested Xo/Xc
.Pp
.Nm add
.Op Fl r | Fl Fl random-key
.Op Fl Fl random-password
.Op Fl p Ar string \*(Ba Fl Fl password= Ns Ar string
.Op Fl Fl key= Ns Ar string
.Op Fl Fl max-ticket-life= Ns Ar lifetime
.Op Fl Fl max-renewable-life= Ns Ar lifetime
.Op Fl Fl attributes= Ns Ar attributes
.Op Fl Fl expiration-time= Ns Ar time
.Op Fl Fl pw-expiration-time= Ns Ar time
.Ar principal...
.Bd -ragged -offset indent
Adds a new principal to the database. The options not passed on the
command line will be promped for.
.Ed
.Pp
.Nm add_enctype
.Op Fl r | Fl Fl random-key
.Ar principal enctypes...
.Pp
.Bd -ragged -offset indent
Adds a new encryption type to the principal, only random key are
supported.
.Ed
.Pp
.Nm delete
.Ar principal...
.Bd -ragged -offset indent
Removes a principal.
.Ed
.Pp
.Nm del_enctype
.Ar principal enctypes...
.Bd -ragged -offset indent
Removes some enctypes from a principal; this can be useful if the
service belonging to the principal is known to not handle certain
enctypes.
.Ed
.Pp
.Nm ext_keytab
.Oo Fl k Ar string \*(Ba Xo
.Fl Fl keytab= Ns Ar string
.Xc
.Oc
.Ar principal...
.Bd -ragged -offset indent
Creates a keytab with the keys of the specified principals.
.Ed
.Pp
.Nm get
.Op Fl l | Fl Fl long
.Op Fl s | Fl Fl short
.Op Fl t | Fl Fl terse
.Op Fl o Ar string | Fl Fl column-info= Ns Ar string
.Ar principal...
.Bd -ragged -offset indent
Lists the matching principals, short prints the result as a table,
while long format produces a more verbose output. Which columns to
print can be selected with the
.Fl o
option. The argument is a comma separated list of column names
optionally appended with an equal sign
.Pq Sq =
and a column header. Which columns are printed by default differ
slightly between short and long output.
.Pp
The default terse output format is similar to
.Fl s o Ar principal= ,
just printing the names of matched principals.
.Pp
Possible column names include:
.Li principal ,
.Li princ_expire_time ,
.Li pw_expiration ,
.Li last_pwd_change ,
.Li max_life ,
.Li max_rlife ,
.Li mod_time ,
.Li mod_name ,
.Li attributes ,
.Li kvno ,
.Li mkvno ,
.Li last_success ,
.Li last_failed ,
.Li fail_auth_count ,
.Li policy ,
and
.Li keytypes .
.Ed
.Pp
.Nm modify
.Oo Fl a Ar attributes \*(Ba Xo
.Fl Fl attributes= Ns Ar attributes
.Xc
.Oc
.Op Fl Fl max-ticket-life= Ns Ar lifetime
.Op Fl Fl max-renewable-life= Ns Ar lifetime
.Op Fl Fl expiration-time= Ns Ar time
.Op Fl Fl pw-expiration-time= Ns Ar time
.Op Fl Fl kvno= Ns Ar number
.Ar principal...
.Bd -ragged -offset indent
Modifies certain attributes of a principal. If run without command
line options, you will be prompted. With command line options, it will
only change the ones specified.
.Pp
Possible attributes are:
.Li new-princ ,
.Li support-desmd5 ,
.Li pwchange-service ,
.Li disallow-svr ,
.Li requires-pw-change ,
.Li requires-hw-auth ,
.Li requires-pre-auth ,
.Li disallow-all-tix ,
.Li disallow-dup-skey ,
.Li disallow-proxiable ,
.Li disallow-renewable ,
.Li disallow-tgt-based ,
.Li disallow-forwardable ,
.Li disallow-postdated
.Pp
Attributes may be negated with a "-", e.g.,
.Pp
kadmin -l modify -a -disallow-proxiable user
.Ed
.Pp
.Nm passwd
.Op Fl r | Fl Fl random-key
.Op Fl Fl random-password
.Oo Fl p Ar string \*(Ba Xo
.Fl Fl password= Ns Ar string
.Xc
.Oc
.Op Fl Fl key= Ns Ar string
.Ar principal...
.Bd -ragged -offset indent
Changes the password of an existing principal.
.Ed
.Pp
.Nm password-quality
.Ar principal
.Ar password
.Bd -ragged -offset indent
Run the password quality check function locally.
You can run this on the host that is configured to run the kadmind
process to verify that your configuration file is correct.
The verification is done locally, if kadmin is run in remote mode,
no rpc call is done to the server.
.Ed
.Pp
.Nm privileges
.Bd -ragged -offset indent
Lists the operations you are allowed to perform. These include
.Li add ,
.Li add_enctype ,
.Li change-password ,
.Li delete ,
.Li del_enctype ,
.Li get ,
.Li list ,
and
.Li modify .
.Ed
.Pp
.Nm rename
.Ar from to
.Bd -ragged -offset indent
Renames a principal. This is normally transparent, but since keys are
salted with the principal name, they will have a non-standard salt,
and clients which are unable to cope with this will fail. Kerberos 4
suffers from this.
.Ed
.Pp
.Nm check
.Op Ar realm
.Pp
.Bd -ragged -offset indent
Check database for strange configurations on important principals. If
no realm is given, the default realm is used.
.Ed
.Pp
When running in local mode, the following commands can also be used:
.Pp
.Nm dump
.Op Fl d | Fl Fl decrypt
.Op Fl f Ns Ar format | Fl Fl format= Ns Ar format
.Op Ar dump-file
.Bd -ragged -offset indent
Writes the database in
.Dq machine readable text
form to the specified file, or standard out. If the database is
encrypted, the dump will also have encrypted keys, unless
.Fl Fl decrypt
is used.
.Pp
If
.Fl Fl format=MIT
is used then the dump will be in MIT format.
This option may be used if you require that all principal
passwords be changed after loading the dump into an MIT KDC database.
.Pp
If
.Fl Fl format=<keytab-file>
is used, the
.Dq <keytab-file>
should hold the master key for the
MIT KDC (usually a file called /var/db/krb5kdc/.k5.YOUR.REALM).
This will cause the keys to be re-encrypted in the MIT master
key as well as doing the dump in MIT format.
When this dump is loaded into the MIT KDC's database,
the principals that had at least one strong encryption type
key should work and any keytabs for those principals should still work.
The principcals with only weak encryption keys will require a
.Dq change_password
be done on the MIT KDC to get them working.
The
.Fl Fl decrypt
flag is meaningless for this case.
.Ed
.Pp
.Nm init
.Op Fl Fl realm-max-ticket-life= Ns Ar string
.Op Fl Fl realm-max-renewable-life= Ns Ar string
.Ar realm
.Bd -ragged -offset indent
Initializes the Kerberos database with entries for a new realm. It's
possible to have more than one realm served by one server.
.Ed
.Pp
.Nm load
.Ar file
.Bd -ragged -offset indent
Reads a previously dumped database, and re-creates that database from
scratch.
.Ed
.Pp
.Nm merge
.Ar file
.Bd -ragged -offset indent
Similar to
.Nm load
but just modifies the database with the entries in the dump file.
.Ed
.Pp
.Nm stash
.Oo Fl e Ar enctype \*(Ba Xo
.Fl Fl enctype= Ns Ar enctype
.Xc
.Oc
.Oo Fl k Ar keyfile \*(Ba Xo
.Fl Fl key-file= Ns Ar keyfile
.Xc
.Oc
.Op Fl Fl convert-file
.Op Fl Fl master-key-fd= Ns Ar fd
.Bd -ragged -offset indent
Writes the Kerberos master key to a file used by the KDC.
.Ed
.\".Sh ENVIRONMENT
.\".Sh FILES
.\".Sh EXAMPLES
.\".Sh DIAGNOSTICS
.Sh SEE ALSO
.Xr kadmind 8 ,
.Xr kdc 8
.\".Sh STANDARDS
.\".Sh HISTORY
.\".Sh AUTHORS
.\".Sh BUGS
